The easiest and least expensive would be check by replacing your dash HVAC unit to see if any improvement occurs. The more expensive, and likely fix is a replacement of the blower motor voltage regulator and, since you're that far into the repair, also blower motor. It's not a tough job. There's lots of posts about how to do it ( I believe that I've done a post on it 3-4 years ago). While you're at it, I recommend that you also clean and re-lube your mono-wiper external and internal assembly. Let us now how it turned out.


AL

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03 CLK430 Cabrio 211K Pweter Silver/ Oyster Leather
90 300SEL 214k Pearl Black/ Alto Grey/Black Leather

Prior: 85 190E, 88 300TE, 89 300TE, 90 300E 2.6, 90 300TE, 92 300E 2.6, 91 and 93 300SL, 87 Ferrari Mondial Cabrio